I live in a rural city near the southwestern end of the Korean Peninsula and make occasional visits to the capital (Seoul). The two cities are roughly 300km (190 miles) apart, which means I only need to make a charging stop once during a round trip. Having owned the Bolt for nearly 18 months, and having more or less settled on the "style" of driving for the better half of the year it has now become possible to compare the efficiency values of the recent trips on more or less equal grounds.
March 2019
6.50km/kWh @ 5-10C
6.71km/kWh @ 10C
June 2019
7.76km/kWh @ 25C
7.41km/kWh @ 22C
7.53km/kWh @ 27C, rain
7.93km/kWh @ 30C
August 2019
7.03km/kWh @ 26-28C, heavy rain
7.96km/kWh @ 28-30C
September 2019
7.83km/kWh @ 28C
7.77km/kWh @ 18-22C, light rain
October 2019
6.86km/kWh @ 6-8C
7.59km/kWh @ 13-16C
The trips are made mostly (about 80 to 90%) on the expressways with the cruise control set at 100km/h, which is actually 95km/h (59mph) according to the GPS. I avoid using heater or air conditioning. During the very hot summer days the usage went up to 4% of total power consumption, but for the rest of the times it's around 1% at most.
So, the driving style and conditions, as well as interior climate control settings are kept nearly identical. Therefore I concluded that the factors affecting the results pretty much come from the outside, namely ambient temperature and precipitation.
As for the rain, it seems to affect up to roughly 10% of the efficiency. Not surprising, but it was nice to confirm how much of a drag it can be. This could be used for future trip planning.
For the temperature, it seems that Bolt performs optimally around 20 to 30C (68 to 86F), posting mid to high 7 in general. But if the temperature drops to 10C (50F) the efficiency falls below 7. I don't think it's the colder temperature affecting the battery efficiency; at least, not at this temperature range. I can clearly see that the motor consumes more energy at the same speed - about 13kW vs 14 to 15kW at the aforementioned 100km/h cruise setting and there's zero battery conditioning involved.
The only reason I can think of as the cause of this is the air getting denser with lower temperature. Bolt needs to push harder, hence needing more energy. But in any case the observations provide me with good baseline for trip planning. If it's cold outside, expect a hit in the range even if you don't turn on the heater.
March 2019
6.50km/kWh @ 5-10C
6.71km/kWh @ 10C
June 2019
7.76km/kWh @ 25C
7.41km/kWh @ 22C
7.53km/kWh @ 27C, rain
7.93km/kWh @ 30C
August 2019
7.03km/kWh @ 26-28C, heavy rain
7.96km/kWh @ 28-30C
September 2019
7.83km/kWh @ 28C
7.77km/kWh @ 18-22C, light rain
October 2019
6.86km/kWh @ 6-8C
7.59km/kWh @ 13-16C
The trips are made mostly (about 80 to 90%) on the expressways with the cruise control set at 100km/h, which is actually 95km/h (59mph) according to the GPS. I avoid using heater or air conditioning. During the very hot summer days the usage went up to 4% of total power consumption, but for the rest of the times it's around 1% at most.
So, the driving style and conditions, as well as interior climate control settings are kept nearly identical. Therefore I concluded that the factors affecting the results pretty much come from the outside, namely ambient temperature and precipitation.
As for the rain, it seems to affect up to roughly 10% of the efficiency. Not surprising, but it was nice to confirm how much of a drag it can be. This could be used for future trip planning.
For the temperature, it seems that Bolt performs optimally around 20 to 30C (68 to 86F), posting mid to high 7 in general. But if the temperature drops to 10C (50F) the efficiency falls below 7. I don't think it's the colder temperature affecting the battery efficiency; at least, not at this temperature range. I can clearly see that the motor consumes more energy at the same speed - about 13kW vs 14 to 15kW at the aforementioned 100km/h cruise setting and there's zero battery conditioning involved.
The only reason I can think of as the cause of this is the air getting denser with lower temperature. Bolt needs to push harder, hence needing more energy. But in any case the observations provide me with good baseline for trip planning. If it's cold outside, expect a hit in the range even if you don't turn on the heater.
